This invention concerns a roll for use in business machines and, more particularly, it relates to a roll suitably used for removing residual toners on the photosensitive drum in dry process copying machines.
Rolls made of silicone rubber have generally been used as the roll for removing residual toners on the photosensitive drum in dry process copying machines (cleaning roller). As shown in FIG. 3, the silicone rubber roll comprises an inner layer 2 made of foamed silicone rubber formed to the circumference of a larger diameter body portion 1a at the middle part of a metal shaft 1 and a surface layer 3 made of non-foamed silicone rubber disposed along the circumference of the inner layer 2.
However, the silicone rubber roller mentioned above involves the following problems:
(1) Since expensive silicone rubber is used as the material and the inner and outer layers are formed separately, the production cost is considerably high. PA0 (2) The use of highly heat resistant silicone rubber is not reasonable but wasteful in view of the balance between the required performance and the properties of the material since the material used for the cleaning roller has only to withstand the temperature of about 50.degree. C. as the operation temperature of the photosensitive drum. However, since no satisfactory materials have been available with respect to the moderate elasticity and releasing property required upon cleaning, the use of the silicone rubber has been inevitable.